The NYUCI Proteomics Facility provides state-of the-art biologica lmass spectrometry analyses to NYU scientists to help them identify and characterize proteins of medical importance. The facility has identified thousands of proteins from SDS-PAGE gels, often by de novo sequencing by Q-TOF MS/MS of proteins present at subpicomolar levels, followed by MASCOT or BLAST homology database searching. The facility has also characterized posttranslational modifications such as phosphorylation and glycosylation from proteins derived from SDS-PAGE gels. In addition to its technical expertise, one of the strengths of the facility is its ability to advise clients in the design and interpretation of experiments so that useful data can be obtained and meaningful information can be had from these data. Reliance on cutting edge technology and its expert and dedicated staff allow these services to be performed in an extremely cost effective manner. Indeed, many experiments by investigators at NYU and the Kaplan Comprehensive Cancer Center could not have been done without the assistance of the facility.